Collars of the type including two semicircular elements, one fixed element presenting a means for attachment to the wall (such as a screw, sealing flap, or band through which a bolt passes) in its intermediate part and a removable element assembling on the fixed element to lock the collar and secure the pipe is simple and inexpensive, is well suited for supporting pipes in horizontal position, for example on a platform, or for maintaining pipes in vertical position along a wall. It is less well suited for supporting pipes in horizontal position along a wall, because in that case the weight of the pipe is improperly supported and tends to deform the collar. Special supports including a fixed element in hook form dimensioned to support the weight of the pipe are also generally used in the latter case. This concept is technically more satisfactory, but it is more costly than that of the above mentioned collar. Moreover, the installer is compelled to always have these two types of collars in stock or at his disposal in the work yard to make all the installations required.